1. Background of the Invention
The present invention relates generally to a seat frame for use in an automotive vehicle, and more particularly, to the framework for pivotally mounting a seat back frame to a seat base frame.
2. Description of the Related Art
Conventional seating systems typically utilize a pivotal arrangement by which the position of the seat back in relation to the seat base may be varied. Such systems allow the seat back to be placed in discrete positions through either a mechanical apparatus or a power assist mechanism, typically, a screw, hydraulic or pneumatic assembly. Generally, automotive seat frames are of a tubular steel construction wherein the seat back is formed in a continuous U-shaped frame. The ends of the frame are flattened and pivotally connected at each end to a tubular seat base. While providing a satisfactory seat frame from an adjustability standpoint, such a frame fails to provide the necessary rigidity and strength to prevent torsion and flexing during use of the seat. It is known to provide reinforcing plates fastened along one, or both upright sides of the seat back frame to provide reinforcement against bending. While this approach aids in reducing the effects of torsional and bending loads and increases the capacity of the seat frame to accommodate bending and torsional loads, it also adds additional weight to the seat frame and therefore, increases manufacturing and assembly costs, along with increasing the overall weight of the vehicle.
While this approach has some limited uses, it is desired to have a lightweight seat frame which can accommodate bending and torsional loads, while being easily assembled to allow for pivotal adjustment between the seat cushion and seat back.